Cutoff device



C.'D|CE CUTOFF DEVICE Filed June 29, 1940 Sheets-Sheet-l CHARLES DICE.

Feb.9,1943. H E' 2, 10,403

, CUI'OFF DEVICE Filed June 29, 1940 2 Sheets-Sheet? CHARLES DNZE.

Patented Feb. 9, 1943 CUTOFF DEVICE Charles Dice, Mount Vernon, Ohio,assignor to Pittsburgh Plate Glass. Company, Allegheny County, Pa, acorporation of Pennsylvania Application June 29, 1940, Serial No.343,203

8 Claims.

This invention relates to so-called cut-off devices for severing sheetglass during drawing operations, and it has particular relation to astructure which prevents scratching or marring of the glass inconnection with the operation of severing devices.

One object of the invention is to provide an improved arrangement ofcut-01f device which automatically operates to prevent portions of thedevice scratching or otherwise marring the glass.

Another object of the invention is to provide an improved controlmechanism for influencing operation of clamping members in a glasscutoff unit.

Another object of the invention is to provide an improved mechanismwhich is automatically operable in response to movement of a cut-offunit during the operation of the latter to control operation of clampingmembers.

In severing drawn sheet glass, the latter is moved upwardly betweenrolls of conventional drawing apparatus and at a predetermined position,the glass is severed and removed from the apparatus in suitable measuredsections. It is customary to sever the sheet glass by means of out-offunits which are automatically clamped upon opposite sides of the glassand travel concurrently therewith while the cutting operation is inprogress. At the completion of each cutting operation, the unit isautomatically released from clamping relation and lowered to a startingposition.

These cut-01f units must be flexible in order to conform to the movementof the glass without breaking or injuring it. However, certaindisadvantages of scratching or otherwise marring the glass have been acharacteristic of previously known types which, in their incidentalmovements, come in contact with the glass at times other than during theactual clamping operations. The principal feature of this inventioninvolves the incorporation of a control mechanism in a cut-off unitwhich insures rapid and efficient operation of the unit without dangerof scratching the glass. The control mechanism is automatic in itsoperation and responds to the normal operation of the unitwithout in anyway interfering with the proper functioning thereof.

In the drawings:

Fig. 1 is a fragmentary end elevation of a cutoff device in its open orunclamped position as applied to a glass drawing apparatus shown incross section"; Fig. 2 is a fragmentary'elevation similar to Fig. 1, inwhich the cut-off device is shown'in closed position; Fig. '3 is afragmentary side elevation of the structure shown in Fig. 1; Fig. 4 is ahorizontal section taken substantially along the line IVIV of Fig. 2;and Fig. '5 is a horizontal section, on a larger scale, takensubstantially along the line VV of Fig.

In practicing the invention, a cut-off device ill for severing sheetglass l I is mounted in floating relation in connection with aconventional glass drawing apparatus 13 which includes drawing rolls [5engageable upon opposite sides of the glass which travels in asubstantially vertical plane along which the cut-off device isvertically'movable. The general type of cut-01f .device employed isexemplified in U. ,8. Patents Nos. 1,373,533 and 1,973,723, in which acutting unit is automatically controlled at predetermined intervals forproperly cutting the sheet glass as it travels upwardly.

The cut-off device Ill comprises an upper frame structure I 6 whichincludes conventional solenoid structure I! shown diagrammatically inFigs. '1 and 2. Each solenoid structure includes an upwardly movablecore l8 having at its lower end a pair of horizontally slotted portionsH3 in which the inner ends of oppositely disposed bell cranks 20 arepivotally connected, as indicated at 2|. Intermediate portions of thebell cranks are provided with pivotal supports '23 .upon .a lowerportion of the solenoid supporting structure l1. These bell cranksextend outwardly in opposite directions and their outer ends arepivotally connected, as indicated at'25, to the innerends of links 26which have oppositely extending outer ends pivotally connected, asindicated at '21, upon lower portions of suspended arms 30. Pivotalconnections 3| in the frame structure 16 support the arms at their upperends.

Clamping frames 33 having resistance elements 35 arranged horizontallythereon are secured horizontally along the lower portions of the arms30. Adjacent opposite end portions .of the cut-off unit H! are suspendedby means .of cables 38 which are connected to the upper frame structureIt and are trained over pulleys 31 rotatably carried on conventionaloverhead supports 38 forming a part of the drawing apparatus structure.Free ends of the cablesare secured to counterbalancing weights39whosecombined weights are less than the weight of the cut-off unit.However, the latter is sufficiently heavy to insure proper downwardmovement thereof until the arms 30 strike an upperplatform portion 50 ofthe drawing apparatus. This action is not sudden, but more or less inthe form of a settling movement of the units.

Rollers 5| having bearing connections 52 on the lower ends of the armsfacilitate movement of these arms in the closing or clamping action ofthe frames 33. Opposite sides of the solenoid supporting structure I!are provided with oppositely extending latches 53 having pivotalconnections 55 securing them to such structure and these latches arenotched to form thereon shoulders 56 and relatively narrow'fingers 57.The outer ends of the latches extend through slots 58 formed in the arms30 and the fingers 51 normally rest upon the lower walls or extremitiesof the slots. The outer end of the latches constantly tend to movedownwardly under the influence of gravity.

A latch actuating rod 60 is longitudinally slidable in a guide 6| formedcoextensively and rigidly on each arm 30 and the lower end of this rodnormally extends downwardly beyond the roller 5|. A head 63 rigidlysecured to the upper end of each rod 60 has a slotted portion 65 whichfits upon the arm 30 and is movable into engagement with the outer endof the latch 53. When the cut-off unit moves downwardly from the fullline position to broken line position (Fig. 1), the lower ends of therods 60 strike the apparatus platform 50 and are moved upwardly untilthe heads 63 strike the latches 53 and the arms 30 are then free toswing inwardly. This action occurs only in the lower position of theunit.

In the operation of the apparatus, the sheet glass II is movableupwardly and the cut-off unit is disposed in the position indicated inbroken lines of Fig. 1. In the upward movement of the glass, the upperedge of the latter strikes an electric switch 61 which energizes thesolenoid core I8 and causes the frames with the resistance elementsthereon to be clamped upon opposite sides of the glass, as shown inbroken'lines of Fig. 2. The switch is mounted upon a frame portion 68 ofthe glass drawing apparatus. Continued movement of the glass carries thecounterweighted unit upwardly therewith until the resistance elementshave rendered the glass severable along the line of engagementtherewith. It is, of course, to be understood that the type of cuttingelement employed may be in the form of an electric resistance element ora conventional cutting tool, both of which are shown in the U. S.patents mentioned above.

Upon movement of the cut-off device upwardly a predetermined distance,it actuates a switch 69 and causes the solenoid to be de-energized. Thenthe arms 30 automatically swing outwardly away from the glass. Theswitch 69 is also mounted upon a frame portion 68 of the glass drawingapparatus. In order to prevent continued swinging 0r oscillation of thearms 30, the latches drop by gravity to such position that the latchshoulders 56 engage the arms when the latter reach their outwardly swungposition shown in full lines of Fig. 1. They are held in this outwardlyswung position until released by the rods 60. This action is automaticand as the cut-off device which has been freed from clamping relationdrops automatically and relatively slowly by gravity, the section ofglass severed can be removed. When the rods 60 strike the platform 59,they move upwardly and release the latches to present the apparatus incondition for the succeeding similar cycle of operation as described.

It is to be understood that the electric switches B1 and 69, togetherwith the solenoid structure I1, are included in conventional electriccircuits, the specific description of which is not necessary forpractical application of the invention described above.

Although only one form of the invention has been shown and described indetail, it will be apparent to those skilled in the art that theinvention is not so limited, but that various changes can be madetherein without departing from the spirit of the invention or from thescope of the appended claims.

I claim:

1. In a cut-off unit for severing sheet glass, a pair of members movableinwardly toward and outwardly away from each other for clamping sheetglass therebetween, a support provided with means pivotally suspendingeach of said members thereon, locking mechanism mounted on the supportand provided with means engagable with the members in response tooutward movement of the latter for releasably locking the members inoutwardly swung positions, and a device movably mounted on each memberand engagable with the locking mechanism to release said members fromtheir outwardly swung positions.

2. In a glass cut-off apparatus, a frame having counterweight mechanismfor suspending it in vertically movable relation along a path of drawingof sheet glass, oppositely disposed depending arms pivotally suspendedfrom the frame and swingable toward and away from the vertical plane ofdrawing of the sheet glass to clamp the latter, locking mechanismdisposed adjacent said arms and movably supported on the frame, saidlocking mechanism and arms including engagable parts responsive tooutward swinging movement of the arms for releasably locking the latterin outwardly swung positions.

3. In a glass cut-off apparatus, a frame having counterweight mechanismfor suspending it in vertically movable relation along a path of drawingof sheet glass, oppositely disposed depending arms pivotally suspendedfrom the frame and swingable toward and away from the vertical plane ofdrawing of the sheet glass to clamp the latter, locking mechanismengageable with said arms and movably supported on the frame, to locksaid arms in outwardly swung positions, releasing means connected tosaid arms, said locking mechanism and releasing means including coactingparts relatively movable in response to vertical movement of said frameto release the arms from their outwardly locked positions.

4. In a vertically movable cut-off unit for severing sheet glassincluding apparatus for drawig sheet glass in a vertical plane, clampingmembers swingable toward and from the glass, means for mounting saidmembers in swinging relation, locking mechanism disposed adjacent theclamping members and movably supported on said means, said lockingmechanism and clamping members including engageable parts responsive tooutward swinging movement of the clamping members for releasably lockingthe latter in outwardly swung positions, releasing means connected tosaid clamping members, said locking mechanism and releasing meansincluding c'oacting parts relatively movable in response to downwardmovement of said unit to release the clamping members from theiroutwardly locked relation.

5. In a cut-01f unit for severing sheet glass, a frame movable betweenupper and lower positions, supporting structure carrying the frame inits upward and downward movement, a pair of member swingable inwardlytoward and outwardly away from each other for clamping sheet glassbetween them, means for pivotally mounting said members upon said frame,locking mechanism mounted on the frame, said mechanism and membersincluding coacting elements engageable in response to outward movementof the members for releasably locking the latter in outwardly disposedpositions, and a device movably mounted on each member and engageablewith the locking mechanism to release said members from their outwardlydisposed positions.

6. In a cut-off unit for severing sheet glass, a frame movable betweenupper and lower positions, supporting structure carrying the frame inits upward and downward movement, a pair of members swingable inwardlytoward and outwardly away from each other for clamping sheet glassbetween them, means for pivotally mounting said members upon said frame,locking mechanism mounted on the frame, said mechanism and membersincluding coacting elements engageable in response to outward movementof the members for releasably locking the latter in outwardly disposedpositions, downwardly disposed releasing means operatively connected tosaid members, and a stationary element arranged in operative relationwith said releasing means and against which the latter strikes inresponse to movement of the frame to its lower position to release saidmechanism from locked relation with said members.

'7. In a cut-off unit for severing sheet glass, a frame movable betweenupper and lower positions, supporting structure carrying the frame inits upward and downward movement, a pair of members swingable inwardlytoward and outwardly away from each other for clamping sheet glassbetween them, means for pivotally mounting said members upon said frame,locking mechanism mounted on the frame, said mechanism and membersincluding coacting elements engageable in response to outward movementof the members for releasably locking the latter in outwardly disposedpositions, a stationary part disposed below the frame and limitingdownward movement thereof, and a device slidable on each of said membersand extending below the lower extremity thereof and movable downwardlywith the frame into engagement with the stationary part to actuate thelocking mechanism out of locked relation with the members.

8. In a glass cut-off unit for severing sheet glass, a frame movablebetween upper and lower positions, supporting structure carrying theframe in its upward and downward movement, a pair of members swingableinwardly toward and outwardly away from each other for clamping sheetglass between them, means for pivotally mounting said members upon saidframe, looking mechanism mounted on the frame, said mechanism andmembers including coacting elements engageable in response to outwardmovement of the members for releasably locking the latter in outwardlydisposed positions, a stationary part disposed below the frame andlimiting downward movement thereof, a device slidable on each of saidmembers and extending below the lower extremity thereof and movabledownwardly with the frame into engagement with the stationary part toactuate the locking mechanism out of locking relation with the members,and rollers on the lower portions of the members adapted to rest on saidstationary part while the frame is in its lower position.

CHARLES DICE.

